Permanent well completion apparatus



May 2, 1961 J. w. KENNEDAY PERMANENT WELL COMPLETION APPARATUS Filed March 3, 1958 INVENTOR. JOHN w. KENNEDAY, BY; Z i i viiimha ATTORNEY.

I a I t I 2,982,357 I PERMANENT WELL COMPLETION APPARATUS assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Filed Mar. 3, 1958, Ser- No. 718,630

- United States Patent O John W. Kenneday, Houston, Tex., assignor, by mesne 2,9 2,357 Patented May 2, 1961 'ice 2 with and is in fluid communication with tubing string above opening 16. The lower open end of tubing 17 extends from above productive interval 11 to adjacent productive interval 12. An upper packer 20 is arranged in casing 10 adjacent the lower end of tubing string 15.

, Packer 20 also surrounds offset tubing 17 and is adapted to close off the space between tubing 17 and tubing 15 and casing 10 above productive interval 11. A lower packer 21, provided with dual bores 22 and 23, is arranged adjacent the lower end of tubing 17 and is adapted to close oh the space between bores 22 and 23 and casing 10. Bore 23 of packer 21 is provided with a landing recess 24, and tubing string 15 is provided with a landing nipple 25 arranged above opening 16 adjacent the connection of tubing string 17 and tubing string 15.

Referring particularly to Fig. 1, a flow directing plug is positioned in bore 23 of packer 21. Plug 30 is provided with hanger assembly 26 adapted to engage with landing recess 24 and sealing means 31 adapted to seal 011 the annulus between bore 23 and plug 30. An open-ended flow directing choke 35 is arranged in tubing stringlS. Choke 35 is provided with a hanger assembly an adapted to engage landing nipple 25 and upper and lower sealing means 36 and 37 adapted to seal ofi the annulus between choke35 and tubing string 15 above the ottset tubing 17 connection to tubing string 15 and below opening 16, respectively. This arrangement of apparatus is employed when it is desired to produce interval or zone 12 through the casing above packer 20 and it is desired to produce productive interval 11 through tubing string 15. Thus, as indicated by the arrowed lines, production fluids from interval 12 flow up oifset tubing 17 through opening 16 in tubing string 15 and thence upwardly through casing 10; that is, through the annulus between casing 10 and tubing string 15 and production fluids from productive interval 11 flow upwardly through choke 35 and tubing string 15 to the surface of the earth.

The Fig. .1 illustration embodies crossover flow. For straight flow reference is made to Fig. 2. The apparatus herein is the same as in Fig. 1 except a flow directing choke 40 has been substituted for choke 35. Choke 40 is provided with an open upper end, a closed lower end, upper and lower sealing means 41 and 42, respectively, openings 43 arranged between sealing means 41 and 42 and a hanger assembly 46 adapted to engage landing nipple 25. Sealing means 41 is arranged above the connec tion of offset tubing 17 to tubing string 15 and adapted, to seal off the annulus between choke 40 and tubing string 15. Sealing means 42 is arranged below the connection of offset tubing 17 to tubing string 15 and above opening 16 in tubing string 15 and adapted to seal off the annulus between choke 40 and tubing string 15; and openings 43 fluidly. communicate tube 17 and the interior of choke 40. As shown by the arrows, with this arrangement of apparatus production fluids from productive zone 12 flow upwardly through oflset tubing 17, choke 40, and tubing string 15 to the surface of the earth and production fluids from upper productive interval 11 flow upwardly through the lower open end of tubing string 15, through opening 16 and upwardly through the annulus between tubing string 15 and casing 10.

In Fig. 3 is shown an arrangement of apparatus for working over and servicing lower zone 12. The arrangement of apparatus is the same as in Figs. 1 and 2 except that a tubular extension 45 has been substituted for plug 3 Claims. ((Il. 166-415) This invention relates to permanent well completion apparatus for producing a plurality of spaced-apart hydrocarbon productive intervals and for working over and servicing the lower productive interval of upper and lower productive intervals.

In permanent well completion operations a tubing string is set permanently during the life of the well and various producing, workover, and servicing operations are performed through the permanently set tubing string. The workover and servicing operations, generally performed on permanently completed wells include squeeze cementing operations wherein existing perforations below the lower end of the tubing are cemented oliperforating or reperforating by means of wire line guns at the same or different producing zones orintervals, sand washing operations as well as acidizing and other remedial work.

A full discussion of permanent well completion operations is described in Permanent Type Completions and Wire Line Workovers, The Petroleum Engineer, September, 1956. a

Briefly, the invention concerns apparatus for producing, working over, and servicing a cased borehole penetrating a plurality of spaced-apart hydrocarbon productive intervals and includes a tubing string arranged in said borehole, the lower open end of said tubing string being positioned above the uppermost productive interval, an offset tubing connected to said tubing string and in fluid communication therewith arranged in said borehole, the lower open end of said oifset tubing being positioned below said uppermost productive interval, a first packer arranged in said borehole above said uppermost productive interval adapted to close off the space between said ofiset tubing, said tubing string and said casing, a second packer provided with first and second bores arranged in said borehole below said uppermost productive interval and above a lower productive interval; said offset tubing extending through said first bore, and means arranged in said second 45 bore and in said tubing string adjacent said offset tubing adapted to direct fluid flow.

An object of this invention is to provide an improved apparatus for producing a plurality of hydrocarbon productive intervals. A further object of this invention is to provide improved apparatus for working over the lower zone of two spaced-apart productive zones.

These and other objects of the invention will be apparent from the following description of the invention taken in conjunction with the drawings wherein:

Fig. 1 is a cross-sectional view of a well bore having the completion apparatus of the invention arranged therein for producing operations;

Fig. 2 is a cross-sectional view of a well bore having modified completion apparatus of the invention arranged therein for producing operations; and i Fig. 3 is a cross-sectional view of a well bore having the completion apparatus of the invention arranged therein for working over and servicing a lower productive interval.

Referring more particularly to the drawings wherein identical numerals designate identical elements:

In Figs. 1 through 3 is shown a casing 10 penetrating upper and lower productive intervals, designated 11 and 12, respectively. A tubing string 15 is arranged in casing 10 and is formed to provide a lower open end and an opening 16 near the lower end thereof. An ofiset tubing 17 .is also arranged in casing 10. Tubing 17 connests lar extension 45 is provided with a hanger assembly 46 adapted to engage landing nipple 25 and upper sealing means 47 and 48 and lower sealing means 49. Sealing means 47 is adapted to seal oil the annulus between tubing string 15 and tubular extension 45 above the connection between .oflfset tubing 17 and tubing string 15;

3t) and choke 35 (Fig. 1) or choke 40 (Fig. 2). Tubnsealing means 48 is adaptedto seal oil the annulus between tubing string 15 and tubular extension 45 below opening 16 in tubing string 15; and sealing means 49 is adapted to seal off the annulus between tubular extension 45 and the wall of bore 23 of packer 21.

With this arrangement of apparatus upper zone 11 is effectively isolated. When it is desired to work over the lower zone 12 as for example in a cementing operation a cement slurry may be pumped down tubing string 15 through tubular extension member 45 to adjacent productive interval 12. Reverse circulation to wash out excess cement then may be made by flowing fluid down the annulus between tubing string 15 and casing 10, through opening 16 in tubing string 15, into and downwardly through the lower open end of offset tubing 17 into casing below packer 21, and upwardly through tubular extension 45 and tubing string to the surface of the earth.

Having fully described the nature, objects, and elements of my invention, I claim:

I 1. Apparatus for producing a well having a "casing therein extending downwardly and penetrating a plurality of spaced-apart hydrocarbon productive intervals, said casing being perforated adjacent each of said hydrocarbon intervals comprising a first tubing string arranged in said casing and provided with a lower open end positioned above an upper productive interval and an opening intermediate the length thereof; a second tubing string arranged in said casing offset from said first tubing string and extending below said upper productive interval and connected to and fluidly communicating with said first tubing string above said intermediate opening adjacent its upper end; a first packer arranged in said casing above said upper productive interval and below said intermediate opening surrounding and closing off the space between said tubing strings and said casing; a second packer provided with two spaced-apart bores arranged in said casing below said upper productive interval and above a lower productive interval; a flow-directing plug sealingly arranged in one of said bores; said second tubing string sealingly engaging said other bore such that said second packer in conjunction with said plug seals off the second tubing string-casing annulus surrounding said second tubing string and a flow-directing choke arranged in said first tubing string adjacent the fluid communicating connection forming an annulus between said choke and said first tubing string, said choke being open-ended and provided with upper and lower sealing means adapted to seal off the annulus between said choke and said first tubing string, said upper sealing means being above the fluid communicating interconnection between said first and second tubing strings and said lower sealing means being below said intermediate opening whereby separate flow-paths from the upper and lower intervals are established, one path fluidly communicating the lower interval and the earths surface through the second tubing string, intermediate opening and casing-tubing annulus above the first packer, the other path fluidly communieating the upper interval and the earths surface through said choke and said first tubing string.

2. Apparatus for producing a well having a casing therein extending downwardly and penetrating a plurality of spaced-apart hydrocarbon productive intervals, said casing being perforated adjacent each of said hydrocarbon productive intervals comprising a first tubing string arranged in said casing and provided with a lower open-end positioned above an upper productive interval and an opening intermediate the length thereof; a second tubing string arranged in said casing offset from said first tubing string and extending below said upper productive interval and connected to and fluidly communicating with said first tubing string above said intermediate opening adjacent its upper end; a first packer arranged in said casing above said upper productive interval and below said intermediate opening surrounding and closing off the space between said tubing strings and said casing; a second arranged in one of said bores; said second tubing string.

sealingly engaging said other bore such that said second packer in conjunction with said plug seals off the second tubing string-casing annulus surrounding said second tubing string and a flow-directing choke arranged in said first tubing string adjacent the fluid communicating connection between said tubing strings forming an annulus between said choke and said first tubing string, said choke being open at the upper end, closed at the lower end, provided with an opening intermediate the length thereof and provided with upper and lower sealing means adapted to seal off the annulus between said choke and said first tubing string, said upper sealing means being above said fluid communicating connection between said tubing strings and said lower sealing means being below the fluid communicating connection between said tubing strings and above said first tubing string intermediate opening whereby separate flow paths from the upper and lower intervals are established, one path fluidly communicating the lower interval and the earths surface through the second tubing string, choke, and first tubing string, and the other path fluidly communicating the upper interval and the earths surface through the intermediate opening and the casing-tubing string annulus above the first packer.

3. Apparatus for producing a well having a casing therein extending downwardly and penetrating a plurality of spaced-apart hydrocarbon productive intervals, said casing being perforated adjacent each of said hydrocarbon intervals comprising a first tubing string arranged in said casing and provided with a lower open end positioned above an upper productive interval and an opening intermediate the length thereof; a second tubing string arranged in said casing offset from said first tubing string and extending below said upper productive interval and connected to and fluidly communicating with said first tubing string above said intermediate opening adjacent its upper end; a first packer arranged in said casing above said upper productive interval and below said intermediate opening surrounding and closing off the space between said tubing strings and said casing; a second packer provided with two spaced-apart bores arranged in said casing below said upper productive interval and above a lower productive interval; an open-ended tubular extension supported in said first tubing string and extending through the other of said bores forming annuli between said tubular extension and said first tubing string and between said tubular extension and the wall of said other bore, upper and lower sealing means arranged on said tubular extension adapted to seal otf the annulus between said tubular extension and said first tubing string, said upper sealing means being above the fluid communicating interconnection between said tubing strings and said lower sealing means being below said intermediate opening; said second tubing string sealingly engaging one of said bores; and said tubular extension being provided with additional sealing means adapted to seal olf the annulus between said tubular extension member and the wall of said other bore such that said upper interval is isolated between said first and second packers and a fluid circulation flow-path to said lower interval is established through said first tubing string, tubular extension, second tubing string, intermediate opening, and casing-tubing annulus above said first packer.

References Cited in the file of this patent UNITED STATES PATENTS 

